Power-hammer mechanism.



S. V. RAWLINGS.

POWER HAMMER MECHANISM.

APPLICATION FILED 1AN.22.19x-1.

Patented May 15, 1917.

2 SHEETS-SHEET I.

S. V. BAWLINGS.

POWER HAMMER MECHANISM.

APPLICATION man JAN. 22. |917.

1,226,006. y Patented May 15, 1917.

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SAMUEL'V. RAWLINGS, OF CAL'UMET, MICHIGAN.

PGWER-HAMMER MECHANISM.

Specification ofy Letters Patent.

Patented May 15, 1911"?.

Original application filed February 24, 1913, Serial No. 750,389. Divided and this application filed. January 22, 1917. Serial No. 143,561.

To ZZ who/m. t may Concern.'

Bc it known that I, SAMUEL V. RAwLrNes, a citizen of the United States, and a resident of Calumet, county of Houghton, and State of Michigan, have invented certain new and useful Improvements in Power Hammer Mechanism7 of which the following is a specification.

The present application is a division of an earlier application filed by me February 24, 1913, Serial No. 7 50,389, for power hammer mechanism, now Patent No. 1,216,608, dated Feb. 20, 1917.

The present invention relates to power hammer mechanism andr seelrs to provide improved valve mechanism for controlling the operation of the hammer.

ln the drawings, Figure 1 is a longitudinal vertical section of the improved hammer mechanism taken on line 1 1 of Fig. 2. Fig. 2 is a partial plan view with parts shown in horizontal section on the line 2 2 of Fig. 1. Fig. 3 is a central vertical section of the starting and stopping valve similar to that shown in Fig. 1, but with the valve in shifted position. Fig. 4 is a horizontal section with the automatic slide valve similar to that shown in Fig. 2 but with the valve shown in shifted position. Fig. 5 is a view in elevation of the slide valve, parts being shown in section on the lines 5 5 of Figs. 1 and 2. Fig. 6 is a similar view with the slide valve shown at the opposite end of its movement. Fig.7 is a detail section on line 7 7 of Figs. 1 and 2. Fig. 8 is a view in elevation of the piston. Fig. 9 is an end view thereof. Fig. 10 is a detail view of the operating cam for a distributing or slide valve.

rThe improved power hammer mechanism is shown mounted upon a suitable frame 1, a cylinder 2 is provided with an elongated pi ston 3 and a piston rod 4 connected at its outer end to a hammer head 5. rlhe hammer head is rectangular in section and is arranged to reciprocate within a corresponding shaped guide 6 on the frame 1 so that the hammer head and piston are held against oscillating movement.

rlChe cylinder is provided with a front head 7, at its forward end, and, at its rear end with a back head 8, valve chest 9 and back head cover 10. The back head 8 abuts against the rear end flange 11 of the cylin-w der, and is preferably provided with a pro jecting portion 12 (see Fig. 1) which fits within an enlarged rear end of the cylinder bore. -The valve chest 9 is held in place between the back head 8 and the baclr head cover 10, the meeting faces of these parts being machined to form a tight fit and the parts being secured together and to the rear flange 11 of the cylinder by bolts 13 which are arranged on opposite sides of and above the anis of the cylinder. A pair of heavier bolts 14 are arranged on opposite sides of the cylinder and substantially in the plane of its axis. The rear ends of these bolts extend through the parts connected by the bolts 13 and their forward ends extend through lugs 15 on the forward end of the cylinder and through lugs 16 on the front head 7. rlhe front head is preferably provided with a sleeve or bushing 17 and a flanged ring 1S, that fits within the front end of the cylinder bore, is held in place by the front head. This ring serves to hold packing 19 in place about the piston rod 4.

The piston 3 is of considerable length and. at its forward end, is provided with a suitable packing vring 20. The rear end portion of the piston is provided with a bore 21 (see Fig. 9) within which extends a valve operating rock shaft 22. This rock shaft extends through the back head 8 of the cylinder and its rear end is keyed to a hub 23 that is mounted in a suitable seat formed in the back head 8, valve chest 9 and cover 10, as most clearly shown in Fig. 1. The forward end of the rock shaft is provided with laterally projecting lugs 24 which engage radial cam slots 25 formed in the rear portion of the piston3. At their ends, the slots 25 are provided with longitudinally extending portions 26 and 27 having side walls substantially parallel to the axis of lthe piston. rlhe walls of the inclined portion of the slot between the straight portions 26 and 27 are substantially helical surfaces and the lugs 24 on the forward end of the rock shaft 22 are provided with longitudinal and inclined surfaces, as shown in Fig. 10 for engaging the corresponding portions of the slots. The valve operating rock shaft 22 and hub 23 are held against longitudinal movement but are oscillated back and forth by the cam slots in the piston as the latter reciprocated. At the opposite ends of the movement of the piston, the rock shaft is held stationary.

The hub 23 at the rear end of the rock shaft is provided -with a valve operating crank arm 28 which is provided at its upper end with oppositely disposed lugs 29 and 30. These lugs are arranged to engage a pin 31 on the back of a distributing slide valve 32. The valve slides transversely between guides 33 and 34 formed in the upper forward portion of the valve chest and is provided with cavities a and Z) on its forward face. rThe upper portion of the rear face of thevback head 8 forms a seat for the slide valve 32 and is provided with a series of ports or passages (Z, e, j' and g, which are controlled by the slide valve. It should be noted that the space between the lugs 29 and upon the valve operating crank arm 28 is greater than the diameter of the pin 31 so that there is a lost motion connection between the valveJ and its operating arm.

A. valve casing 35 is mounted upon the Seat 36 formed upon the side wall of the cylinder 2 adjacent its rear end. An oscil lating valve 37 arranged within the cylinder bore of the valve casing, has a cavity h on its lower side and is adapted to control a series of three ports j, Za and Z. The upper portion of the cylinder is cored to form the ports or passages m, a, 0V and 7) and the upper portion of the back head 8 is cored to form an exhaust port r that communicates with the ports e and f controlled by the slide valve 32. The port or passage Z leads to the passage ,o in the cylinder and the latter communicates with the back end vof the cylinder bore. The port or passage g of the back head communicates with the passage a that leads to the central port 7c of the starting valve and the passage m of the cylinder leads from the right-hand port Z of the starting valve to the front end of the cylinder bore. The left-hand port of the starting valvey communicates with the passage 0 of the cylinder and the latter communicates with the passage s that extends through the back head 8 into the space within the valve chest. rlhe hack head cover is provided at its upper portion with a transverse recess 38 in its front face that increases the capacity of the. chamber within the valve chest. il supply pipe 39 for air or fluid under pressure communicates with the casing 35 of the starting and stopping valve. The valve itself is provided, outside the casing, with a crank arm l0 and an operating rod l1 by which the valves may be shifted to start and stop the operation of the hammer.

The valve is shown in its idle or non-working position. in Fig. 1 and in its operative position in full lines in Fig. 3. In the first postion, as shown, the cavity Z1. of the valve connects the ports y' and 7c and the port Z is connected to the spacewithin the starting valve casing. ln the operative position of thestarting valve, the cavity connects the ports y' and Z and the port 7c and is connected to the supply within the valve casing. The back end of the cylinder is always connected by the passage 79 to the port 4Z, which opens into the valve chest and is controlled by the slide valve 32 and, in the working position of the starting and stopping valve, the front end of the cylinder is connected to the valve chest through the medium of the passage mi, port Z, cavity Zt of the starting and stopping valve, port Ze, passage a and port g.k In this working position, the supply of air or other fluid under pressure is connected to the valve chestthrough the casing 10, port y' and passages o and s.

lVith the starting and stopping valve in the working positions shown in Fig. 3, the Dperation is as follows:

lWith the piston at the back end of its movement, as shown in Fig. l, the automatic slide valve 32 will be in the position shown in Figs. 2 and 5. The front end of the cylinder will thus be connected to the exhaust port r through the cavity Z) ofthe slide .falve which, in this position, connects the ports f and g, and the back end of the cylinder will be connected to the space within the valve chest, since the slide valve in this position uncovers the port (Z. Air under pressure will therefor be supplied to the back end of the cylinder and the piston 3 and hammer 5 will be projected forwardly to strike the blow. As the piston moves forwardly, the lugs 24rof the rock shaft 22 pass through the inciined or helical portions 25 ofthe cam slots in the piston and the rock shaft and crank arm 28 are oscillated in the direction indicated by the arrow in Fig. 5. This move ment first takes up the lost Vmotion between the lug 30 and the pin 31 of the slide valve. But as the piston approaches the end of its forward stroke, the valve is shifted to the position shown in Figs. -l and 6. The hack end of the cylinder will then be in communication with the exhaust since the cavity a of the slide valve then connects the ports Z and e and the front end of the cylinder will be connected to the supply since, in this position, the slide valve uncovers the port g. This shifting of the valve is effected slightly before the piston reaches the end of its forward movement to cushion the same and prevent the piston from striking violently against the front head. But the valve meclr anism is so timed that the shift of the valve does Vnot take place soon enough to cushion the blow of the hammer. The piston then moves rearwardly and the movement of the valve operating crank arm 28 is reversed. As the piston approaches the rear end of its movement, the lug 29 of the crank arm engages the pin 31 and shifts the valve hack to the position shown in Figs. 2 and 5. This movement of the valve takes place in time to effectively cushion the return stroke of the piston.

When the starting and stopping valve 37 is in the idle position shown in F ig. 1, the front end of the cylinder is cut olf from the valve chest and is placed in direct communication with the source of supply since the passages m and Z then communicate with the interior of the valve casing 35. At this time, the valve 32 is in the position shown in Fig. 2 and the back end of the cylinder is connected to the valve chest. But the source of fluid under pressure to the valve chest through the ports j, 0 and s is cut oli" and communication is established between the valve chest and the exhaust as follows: rlhrough the passages s and o, port j, cavity 72, of the starting and stopping valve, port 7c, passage a and cavity l; ofthe slide valve. lThus in this position of the starting and stopping valve, both the space within the valve chest and the back end of the cylinder are connected to the exhaust and, since, as stated, the front end of the cylinder is connected to the source of supply, the piston is securely held in its withdrawn position until the starting and stopping valve is shifted. As soon as this occurs, the valve chest and the back end of the cylinderl are connected to the supply and the front end of the cylinder to the exhaust so that the piston at once commences its forward stroke and continues its operationas long as the valve 37 is maintained in the working position shown in full lines in Fig. 3. Through the medium of the valve 37 the starting and stopping of the hammer can be very quickly controlled and when the hammer is stopped it is held in withdrawn position with the piston at the back end of the cylinder. This starting and stopping valve is shown in its extreme working position in full lines in Fig. 3, in its eXtreme idle position in dotted lines in Fig. 3 and in an intermediate idle position in Fig. l.

It is obvious that changes may be made in the details set forth without departure from the essentials of the invention as defined in the claims.

l claim as my invention:

l. In a power hammer mechanism, the combination with a cylinder and piston, of a distributing valve for alternately connecting the opposite ends of said cylinder to the supply and exhaust, means controlled by said piston for automatically operating said valve, and a manually controlled starting and stopping valve arranged, in idle position, to connect the forward end of the cylinder to the source of supply, and in working position, to connect the same to a port controlled by said distributing valve.

2. ln a power hammer mechanism, the combination with a cylinder and piston, of

a valve chest, a distributing valve therein for alternately connecting the opposite ends of said cylinder to the supply and exhaust, means controlled by said piston for automatically shifting said distributing valve and a manually operable starting and stoparranged, in working position, to connectv said valve chest to the source of supply and the forward end of said cylinder' to a port controlled by said distributing valve, said starting and stopping valve, in idle posittion, being arranged to connect said valve chest and the rear end of said cylinder to the exhaust and the front end of said cylinder to the source of supply.

l. In a power hammer mechanism, the combination of a cylinder having a valve chest at one end, a piston in said cylinder, a distributing valve in said valve chest for controlling the flow of motive fluid to and from the opposite ends of saidl cylinder, and a rock shaft journaled in the end of said cylinder and having a crank arm engaging 'said valve, said rock shaft and said piston having a cam slot and follo'wer connection for effecting the movement of said valve and said cam slot having straight end portions for holding said rock shaft and valve against movement.

5. ln a power hammer mechanism, the combination of a cylinder, a piston in said cylinder, a distributing slide valve for connecting the opposite ends of said cylinder to the supply and exhaust, an operating rock shaft and an arm on said shaft having a lost motion connection with said valve, said rock shaft and said piston having a camslot and followery connection and said cam slot having straight end portions for holding said rock shaft against movement.

6. ln a power hammer mechanism, the combination of a cylinder, one end of said cylinder having a flat valve seat on its outer face, a valve chest extending over said valve seat, a distributing slide valve mounted in said valve chest and engaging said seat, a piston in said cylinder, and connections between said piston and said distributing valve comprising a rock shaft journaled in and extending through the end of said cylinder and having a cam and follower connection with said piston and a crank arm on said rock shaft directly en-v gaging said valve, said connections being arranged to shift said distributing valve as said piston approaches the opposite ends of its stroke.

7. A power hammer mechanism compris ing a cylinder, a piston in said cylinder, a distributing valve for connecting the opposite ends of said cylinder to the supply and exhaust, a rock shaft extending axially within said cylinder and said piston, and a rock arnron said shaft having a lost niotion connection with said valve, said shaft and said piston having a cam slot and follower connection, substantially as described.

8. In. a power hammer mechanism, the combination with a cylinder and piston, of an automatically operating distributing valve controlling the flow of motive fluid to and from the opposite ends of said cylinder,

and a manually operable starting and stopping valve arranged, in stopping position, to connect the front end of said cylinder to the source of supply for motive fluid and to interrupt the flow of motive fluid to the back end of said cylinder.

9. In ya power hammer mechanism,` the combination with a cylinder and piston, of a valve chest, an automatically operating distributing valve therein, a seat for said valve having two distributing kports and an exhaust port, a starting and stopping valve and a casing therefor connected to the source of supply and having two ports communicating respectively with the front end of said cylinder and said valve chest and an Copies of this patent may be obtained for intermediate port communicating with one of said distributing ports, the other of said distributing ports being in communication with the back end of said cylinder, and said starting and stopping valve being arranged to alternately connect said distributing valve chest and the front end of the cylinder to the source of supply and to said intermediate port.

l0. In a power hammer, the combination of a cylinder, a back cylinder end having a flat valve seat on its outer face provided with cylinder and exhaust ports, a back end cover, an open ended valve chest interposed between and closed by said back cylinder end and said back end cover, tie-bolts securing said parts together and to said cylinder, a piston in said cylinder, a distributing slide valve in said valve chest and engaging said valve seat and operating connections for said valve interposed between the same and said piston.

l1. ln a power hammer, the combination with a cylinder and a piston therein, of a distributing valve controlling the iow of' motive fluid to and from the opposite ends of said cylinder, mechanical connections between said piston and said valve for automatically operating the latter and a starting and stoppin@ valve arranged, in stopping position, to supply motive fluid to the front end of said cylinder and to interrupt the flow of motive fluid to the backend thereof.

SAMUEL VV. RAWLNGS.

five cents each, by addressing the Commissioner of lacents,

Washington, D. C. 

